Pavement cutter



June 2,1970 v. MILLIGAN 3,515,435

PAVEMENT CUTTER Filed Och. 11, 1968 INVENTOR. VIRGIL M. MILLIGAN WV%ATTORN 5 United States Patent 3,515,435 PAVEMENT CUTTER Virgil M.Milligan, P.O. Box 9, Central Valley, Calif. 96019 Filed Oct. 11, 1968,Ser. No. 766,731 Int. Cl. E01c 23/ 09; A01b /18 US. Cl. 29940 3 ClaimsABSTRACT OF THE DISCLOSURE An asphalt pavement cutting disc is removablyattached to the scarifying blade of a grader. The cutting disc ismounted in caster wheel fashion so that it aligns automatically with thedirection of grader movement, allowing the cutting action to occursmoothly along a straight line as well as on a radius or curve asrequired by the steering action imparted to the grader.

BACKGROUND OF THE INVENTION BRIEF SUMMARY OF THE INVENTION According tothe present invention, a rotary cutting disc for asphalt pavementcutting is mounted for castering action about a vertical pivot axis sothat the cutting disc may smoothly follow the contour desired even alonga relatively sharp radius on the road surface, the cutting discautomatically aligning itself according to the direction of movement ofthe associated road grader or the like.

A slight but finite offset is established between the axis of rotationof the cutting disc and the vertical swiveling axis so that a positivecutting action occurs while at the same time achieving a nicety ofalignment allowing the aforesaid sharp radius cutting action to occurwithout imposing undue side stresses upon the cutting disc and itsmounting assembly.

BRIEF DESCRIPTION OF THE DRAWING FIGURES FIG. 1 is a side elevationalview, partly in section, illustrating the rotary cutter disc accordingto the present invention as attached to the mold board of a road graderor the like;

FIG. 2 is a plan view of the assembly shown in FIG. 1, and

FIG. 3 is an enlarged vertical section taken substantially along theplane of section line 33 in FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION With reference now moreparticularly to FIG. 1, a moldboard or scarifying blade 10 of a roadgrader or like piece of equipment is attached by conventional means tothe frame or chassis of the vehicle involved and is provided on itsrearward side with reinforcing plates 12 and 14 interconnected by avertical web plate 16. Attaching ears 18 and 20 are provided on the rearface of the reinforcing plate assembly to project above and below therespective plates 12 and 14, the ears 18 and 20 being positionedadjacent to one or the other of the lateral extremes of the moldboard 10so that a rotary pavement Patented June 2, 1970 cutting disc assembly22, according to the present invention, is correspondingly located withrespect to the scarifying blade or moldboard 10. a

The assembly 22 comprises a mounting bracket 24 including a verticalplate portion 26 and a trailing generally horizontal shelf portion 28.The lower end of the vertical plate portion 26 is provided with anL-shaped jaw member 30 whereas the shelf portion 28 is provided with ajaw member 32 mounted thereon by a pivot pin 34 extending betweenupstanding bracket cars 36 and 38, see FIG. 2. A bolt 40 passes throughthe jaw 32 and threadedly engages in a suitable opening in the shelfportion 28, FIG. 1, so as to urge the jaw member 32 downwardly, wherebythe two jaws 30 and 32 cooperate to clamp the ears 18 and 20 and thussecurely hold the bracket assembly 24 rigidly with respect to themoldboard 10.

The shelf portion 28 is provided with an opening 42, FIG. 3, whichremovably receives a cylindrical housing 44 having an annular flange 46engaging the underside of the shelf portion 28 and provided withopenings in alignment with corresponding openings in the shelf portion28 receiving bolts 48 whereby the housing is rigidly aiiixed to theshelf portion 28. The housing 44 is provided with a vertical bore 50rotatably receiving a spindle 52, the upper end 54 of which is ofreduced diameter and is provided with external threads for receivinglocking nuts 56.

The lower end of the spindle 52 carries an inverted L-shaped arm havinga horizontal portion 58 rigidly afiixed to the spindle, and a verticallydepending portion 60 carrying a stubshaft 62 at its lower end. A sleeve64 is rotatably journalled on the stubshaft 62, the sleeve 64 beingprovided with an annular flange 66 and an extension 68 beyond the flange66 enclosing the stubshaft 62 in its entirety and provided with an endcover plate 70 for sealing the sleeve against the entry of dirt and thelike. The stubshaft 62 is provided with a retaining nut 72 preventingaxial displacement of the sleeve 64 with respect to the stubshaft 62.

A rotary cutting disc 74 is provided with a bolt circle corresponding toopenings in the flange 66 and suitable securing bolts '66 secure thecutting disc 74 removably on the sleeve assembly. The cutting disc 74 isprovided with a sharp edge portion 77 on its periphery whereby topenetrate and cut asphalt pavement in conventional fashion.

As may be seen in FIG. 3, a thrust washer 78 is provided between thestubshaft arm portion 58 and the bottom of the housing 44 and thehousing may be counter- -bored at its upper end to receive a furtherthrust washer 80 against which the locking nuts 56 lightly hear so as toretain the spindle against axial shifting with respect to housing 44while allowing rotary motion of the spindle 52 within the housing. Thehousing at its upper end may include an extension portion 82 to enclosethe upper end 54 of the spindle 52, and closed by a sealing plate 84 toprevent the entry of foreign material into the interior of the housing44. Diagonal stays or reinforcing struts 84 and 86 'may be provided toextend between the portions 26 and 28 of the mounting bracket assembly24.

The arm portion 60 is inclined rearwardly at a slight angle so as toposition the horizontal axis of the stubshaft 62 slightly behind thevertical axis of the spindle 52 so that whereas a major portion of thearea of the cutting disc 74 lies behind the axis of the spindle 52, aminor but substantial portion of the cutting disc 74 lies forwardly ofthe axis of the spindle 52. In this way, a caste-ring action is effectedwithout sacrificing the proper operation or allowing the disc 74 towobble with respect to the direction of movement of the vehicle to whichit is attached. At the same time, the rather mild caster action allowsthe cutter disc 74 smoothly to follow the contour dictated by themovement of the vehicle to which it is attached, thus allowing thecutter blade or disc 74 to follow smoothly and align with the directionof movement even on relatively sharp radius turns as, for eX ample, inthe order of 25 foot radius.

What is claimed is:

1. In combination with a grader vehicle having a generally horizontalscarifier blade, a rotary pavement cutter assembly attached to saidscarifier blade, said assembly comprising,

a mounting bracket member including means for removable attachment tosaid scarifier blade, said bracket having a generally horizontal shelfportion trailing said blade,

a vertical housing fixed to said shelf portion,

a vertically disposed spindle rotatablyreoeived in said housing,

an arm fixed to and depending from said spindle, said arm having ahorizontal stubshaft ofliset rearwardly from the axis of said spindle,

and a cutter discrotatably received on said stubshaft.

2. The rotary pavement cutter according to claim 1 4 wherein said armtrails the axis of said spindle such that, for straight line motion ofthe cutter disc, a substantial but minor portion of the cutter disc liesforwardly of said axis of the spindle.

3. The rotary pavement cutter according to claim 2 'Wherein said arm islaterally offset from said spindle and said stubshaft projects laterallyof said arm, said cutter disc being contained Within a plane alsocontaining the axis of said spindle.

References Cited UNITED STATES PATENTS 172,872 2/ 1876 Ferguson 172-6023,140,898 7/ 1964- Rogers 29940 X 3,271,079 9/1966 Simmons 2994O3,351,139 11/1967 'Schmitz et al. 172602 3,355,214 11/1967 McClure 29940 3,472,554 10/1969 Hopkins 299-40 ERNEST R. PURSER, Primary ExaminerUS. 01. VX.R. 112 502

